Cocaine abuse is a serious public health problem which has been difficult to treat. One of the most effective treatments involves the reinforcement of cocaine abstinence. Abstinence reinforcement procedures derive from an extensive body of laboratory and clinical research in the field of operant conditioning which has shown that drug use can be maintained and modified by manipulating its environmental consequences. We propose to conduct Stage I research to complete development of a novel treatment, a reinforcement-based Therapeutic Workplace, for chronically unemployed, cocaine dependent adults. The Therapeutic Workplace integrates abstinence reinforcement contingencies of proven efficacy into a model supported work program. The critical feature of the intervention is simple: Patients must provide drug free-urine samples to gain entrance to a workplace where they can work and earn salary. This procedure in which two responses are required sequentially (abstinence and then work) to earn salary is called a chained schedule of reinforcement. The chaining is useful because it does not require an independent source of funds to address the abstinence issue, but utilizes work-based salary to reinforce abstinence. The first phase of this treatment (Phase I) is designed to initiate abstinence, teach job skills, and promote professional demeanor. In this critical period, patients earn vouchers instead of cash to reduce the chance that they use earnings to purchase drugs. Phase I has been partially developed and evaluated in a controlled trial which showed that voucher-based salary can reinforce drug abstinence. In Phase II, abstinent and skilled patients will be hired into a business where they will perform real jobs; earn cash salary; and receive random and progressively less frequent drug testing. Phase II will be fully integrated into Baltimore City's welfare-to-work program. We propose to develop Phase II of the intervention, including its integration into Baltimore's welfare-to-work program; to develop a detailed treatment manual for Phases I and II; to computerize most aspects Phases I and II to facilitate their implementation and dissemination to new sites; to conduct a pilot study of a model of the full Therapeutic Workplace intervention; and revise the manual and software based on the results of the pilot study. This research will allow for the development of a novel drug abuse treatment, the Therapeutic Workplace, which could provide a cost-effective means of arranging abstinence reinforcement contingencies of proven efficacy on a wide scale, and could serve as a model program for addressing the often debilitating problem of drug abuse in the nation's welfare-to-work programs.